2006 New York Code - Use Of Rock Support In Lieu Of Underpinning.

 
    §  27-716  Use  of  rock  support  in  lieu  of underpinning. Existing
  structures  founded  at  a  level  above  the  level  of  adjacent   new
  construction  may be supported on hard rock in lieu of underpinning, the
  use of sheeting and bracing, or the  construction  of  retaining  walls,
  provided  that  a  report  by  the  architect  or  engineer is submitted
  substantiating the safety of the  proposed  construction  and  verifying
  that  an  "in-place" inspection has been made of the rock exposed and of
  the jointing therein in the excavation.